Quantitative in vivo1H-spectroscopy of healthy and tumorous human brain tissue at 4 tesla-猫眼课题宝

4 特斯拉下健康和肿瘤人脑组织的体内定量 1H 光谱

DOI：

10.1007/bf03166021

发表时间：

1990

期刊：

Applied Magnetic Resonance

影响因子：

通讯作者：

中科院分区：

物理与天体物理4区

文献类型：

作者：

D. Hentschel;R. Ladebeck;R. Wittig;P. Schüler;G. Schuierer

在 35 名健康志愿者中，测量了顶叶、顶枕叶、额叶、颞叶、丘脑和岛叶区域的 79 个氢谱。在 TE 71、135 和 270 ms 处使用双自旋回波序列选择体素。通过将洛伦兹模型拟合到 3.02 ppm 肌酸库和 3.22 ppm 胆碱库的共振来定量评估光谱。在 6 个研究区域中，两种代谢物的强度均未发现差异。肌酸和胆碱在这些区域中均匀分布。频谱的个体间再现性随着回波延迟的延长而降低。根据采集次数和体素大小校正的肌酸和胆碱面积的变异系数在 TE 71 ms 时为 ±13%，在 TE 135 ms 时为 ±23%，在 TE 270 ms 时为 ±43%。这是由 T2 的个体差异 ±15% 引起的，这会影响频谱的所有共振。每个回波延迟处，来自拟合的信号变化、装载不同对象的射频线圈的 Q 因子以及翻转角度的变化均小于 10%。无需重新定位受试者的个体差异优于 10%。使用肌酸作为内参，2.01 ppm 的 N-乙酰基天冬氨酸 (NAA) 和 2.34 ppm 的谷氨酸 γ-亚甲基质子的振幅比率对于大脑的特殊区域并不具有特异性。仅在颞叶，NAA 和肌酸的比率降低。 NAA 和 Cre 的平均浓度比为 1.7，作为所有受试者和所研究的大脑区域（颞叶除外）的平均值。描述了该方法对 7 名脑肿瘤患者的初步应用。

In 35 healthy volunteers 79 hydrogen spectra were measured from the parietal lobe, parieto-occipital lobe, frontal lobe, temporal lobe, thalamus and insular region. Voxels were selected with a double spin-echo sequence at TE 71, 135 and 270 ms. The spectra were quantitatively evaluated by fitting a Lorentzian model to the resonances of the creatine pool at 3.02 ppm and the choline pool at 3.22 ppm. No differences were found in the intensities of either metabolite in the 6 investigated regions. Creatine and choline were equally distributed in these regions. The interindividual reproducibility of the spectra decreases with longer echo delays. The coefficients of variation of the areas of creatine and choline corrected for the number of acquisitions and the voxel size are ±13% at TE 71 ms, ±23% at TE 135 ms, ±43% at TE 270 ms. This is caused by an interindividual variation in T2 by ±15%, which affects all resonances of a spectrum. Signal variations from the fit, the Q-factor of the RF-coil loaded with different subjects and variations in the flip angle are less than 10% at each echo delay. The intraindividual variation without repositioning of the subject was better than 10%. Using creatine as an internal reference the ratios of the amplitudes of N-acetyl-aspartate (NAA) at 2.01 ppm and γ-methylene protons of glutamic acid at 2.34 ppm were not specific for special regions of the brain. Only in the temporal lobe the ratio of NAA and creatine was reduced. A mean concentration ratio of 1.7 for NAA and Cre was measured as an average over all subjects and the investigated brain regions with the exception of the temporal lobe. Initial applications of the method to 7 patients with brain tumors are described.

Detection of cerebral lactate in vivo during hypoxemia by 1H NMR at relatively low field strengths (1.9 T).